Conserved generator of a continuous quantum symmetry
= Conserved generator of a continuous quantum symmetry
If $U(s)=e^{-isQ/\hbar}$ and $U(s)^\dagger H U(s)=H$, differentiation at $s=0$ gives
$$
[Q,H]=0.
$$
In the <Heisenberg picture>,
$$
\frac{dQ}{dt}=\frac i\hbar[H,Q]=0.
$$